The present invention relates to a positive locking turnbuckle which can be adjusted with relative ease to various lengths in the same manner as a conventional turnbuckle and which may be positively locked at any one of a number of adjustments by a captured locking mechanism.
Turnbuckles are used on marine and other equipment as a connector between cables and similar objects or between dissimilar objects such as the stays and hull of a boat. The turnbuckles have an adjustable length which permits the interconnected objects to be held together by the turnbuckle with a preselected separation or with a predetermined tension. Turnbuckles are used in many different fields because by being adjustable, they accommodate a broad range of tolerances, and they permit objects to be initially interconnected in a loose fashion and subsequently placed in tension.
Because a conventional turnbuckle is fundamentally locked in a predetermined adjustment only by means of the friction between threaded parts, there is always the possibility of the adjustment being lost which, in itself, may be undesirable and which in some circumstances could produce a dangerous or unsafe condition. To avoid such results, some prior art turnbuckles have been provided with locking mechanisms to prevent inadvertent loss of a previously established adjustment and a resulting unsafe condition. U.S. Pat. Nos. 2,694,586 and 3,081,116 are representative of two such patents. In the more recent patent, the terminal members are locked with the barrel of the turnbuckle by means of cotter pins. In the earlier patent, a specially formed resilient sleeve or spring is mounted on the barrel and includes locking flanges which project through a slot in the barrel and engage a corresponding slot in the terminal member at each end of the barrel. In these two patents, changes in adjustment are executed either by removing the cotter pins or withdrawing the locking flanges and rotating the barrel and terminal members relative to one another.
It is a general object of the present invention to provide a turnbuckle having positive locking features such as disclosed in the cited prior art patents and which at the same time is easy to operate, and is comprised of relatively standard parts and in which the locking mechanism remains attached to the turnbuckle at all times so that the mechanism will not be readily lost when the turnbuckle is adjusted.